Other names

Type section

The Kellerville Till Member is named for roadcut exposures 2 miles southwest of Kellerville in the Washington Grove School Section (table 6), NW NW SW Sec. 11, T. 2 S., R. 5 W. The Kellerville Till is also described in the Cottonwood School, Enion, and Tindall School Sections (table 6).

Table 6 -- Stratigraphic Sections (partial)The following 21 stratigraphic sections describe exposures in Illinois and illustrate many of the aspects of Pleistocene stratigraphy. These sections contain the type localities for 21 rock-stratigraphic units, 4 soil-stratigraphic units, and 3 time-stratigraphic units and include paratypes for several other units. The sample numbers preceded by "P" are the numbers used in the Illinois State Geological Survey collections. Analytical data on many of these samples are on file at the Survey. The sections are arrange alphabetically by name.

Chapin Section and Cottonwood School Section

Cottonwood School Section (cont.) and Enion Section

Enion Section (cont.), Farm Creek Section, and Flat Rock Section

Flat Rock Section (cont.), Gale Section, and Jubilee College Section

Pulleys Mill Section, Rochester Section, and Tindall School Section

Tindall School Section (cont.) and Toulon Section

Toulon Section (cont.), Washington Grove Section, and Wedron Section

Stratigraphic relationships

The Kellerville Till is bounded at the base by the Petersburg Silt or, in its absence, by the top of the Yarmouth Soil. Its upper limit is the top of the Pike Soil (New Salem Northeast, Pleasant Grove Sections, table 6), the Duncan Mills Member, the Teneriffe Silt, or younger stratigraphic units.

Table 6 -- Stratigraphic Sections (partial)The following 21 stratigraphic sections describe exposures in Illinois and illustrate many of the aspects of Pleistocene stratigraphy. These sections contain the type localities for 21 rock-stratigraphic units, 4 soil-stratigraphic units, and 3 time-stratigraphic units and include paratypes for several other units. The sample numbers preceded by "P" are the numbers used in the Illinois State Geological Survey collections. Analytical data on many of these samples are on file at the Survey. The sections are arrange alphabetically by name.

Extent and thickness

It is as much as 150 feet thick in the deeper bedrock valleys, but it more commonly is 50 to 100 feet thick. Its geographic extent is shown in figure 6, and its spatial relationship is indicated diagrammatically in figure 7.

Fig. 6 -- Areal distribution of the dominantly till formations and members of Illinois.

Fig. 7 -- Diagrammatic cross section showing the relations of formations and members of Illinoian age in western Illinois.

Lithology

The member consists of till with intercalated discontinuous zones of sand and gravel outwash and silt; it is more variable than the overlying tills and commonly has a significantly higher percentage of expandable clay minerals. The grain-size and clay mineral composition of the matrix is given in tables 2 and 5, and the average of heavy mineral analyses is given in table 4.